固定化混合菌利用戊糖和己糖共发酵制备乙醇  

Co-fermentation of pentose and hexose to ethanol by immobilized mixed yeasts method

作　　者：江枫[1] 房伶晏 王浩[1] 朱均均[1] 范一民[1] 宋向阳[1] 

机构地区：[1]南京林业大学化学工程学院,南京210037

出　　处：《林业工程学报》2017年第4期90-95,共6页Journal of Forestry Engineering

基　　金：国家自然科学基金(30871992);江苏高校优势学科建设工程资助项目(PAPD)

摘　　要：为研究固定化混合菌种对戊糖和己糖同步发酵生产燃料乙醇的影响,以海藻酸钙为固定化载体,采用包埋法固定化休哈塔假丝酵母(Candida shehatae)和酿酒酵母(Saccharomyces cerevisiae)混合菌发酵生产燃料乙醇,并对固定化混合菌种的发酵条件进行优化。结果表明:固定化混合菌种发酵可以快速利用葡萄糖,解除葡萄糖代谢对木糖代谢的抑制作用,提高发酵效率,发酵时间从固定化单菌发酵的24 h缩短至20 h,发酵时间缩短16.67%。乙醇产量从13.28 g/L增加至14.89 g/L,升高了12.12%。固定化混合菌种的优化条件为:混合糖(葡萄糖和木糖)质量浓度为45 g/L,发酵温度为30℃,摇床转速为170 r/min,休哈塔假丝酵母和酿酒酵母菌体的比例为4∶1。在此条件下得到最佳乙醇产量为15.21 g/L,较优化前(13.74 g/L)提高了10.70%。本研究结果可为固定化混合菌发酵生产燃料乙醇的工业化提供理论依据。To study the effect of immobilized multi-microorganisms method on ethanol fermentation, strains of Candidashehatae and Saccharomyces cerevisiae were immobilized on calcium alginate by embedding technology for the simul-taneous fermentation of pentose and hexose. Meanwhile, the fermentation conditions of immobilized mixed multi-mi-croorganisms were optimized. The results showed that the immobilization of C. shehatae and S. cerevisiae rapidly in-creased the rate of glucose consumption and effectively relieved the inhibition of xylose consumption caused byglucose metabolism. Specifically, compared with that of individually immobilized C. shehatae, the fermentation timeof immobilized mixed yeast decreased from 24 h to 20 h, which reduced by 16. 67%. The yield of ethanol increasedfrom 13.28 g/L to 14. 89 g/L, which increased by 12.12%. The optimal conditions of immobilized mixed yeast are asfollows： 45 g/L of mixed sugar （glucose and xylose） as carbon source, fermentation temperature of 30℃, shakingspeed of swing bed at 170 r/min, and the inoculation ratio of C. shehatae and S. cerevisiae at 4：1. Under the abovefermentation conditions, the maximum yield of 15.21 g/L total ethanol was achieved from the simultaneous fermenta-tion of pentose and hexose. The yield of ethanol increased by 10.70% with the immobilized mixed multi-microorgan-isms method. The results of this study could provide some basic information for the industrialization of produce ethanolby immobilized mixed yeast method.

关 键 词：休哈塔假丝酵母 酿酒酵母 固定化细胞 混菌发酵 优化 

分 类 号：TQ920.6[轻工技术与工程—发酵工程]